/**
 * @author：刘东
 * @created: 2013-6-13 下午02:57:47 
 * @version：$Id$ 
 * @since:1.0
 * @copyright 
 *
 */

public class toUtf8String {

	/**
	 * @param args
	 */
	private static final char[] hexDigit = {
		'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A',

		'B', 'C', 'D', 'E', 'F' };

	private static char toHex(int nibble) {

		return hexDigit[(nibble & 0xF)];

	}

	public static String toEncodedUnicode(String theString, boolean escapeSpace) {
		int len = theString.length();

		int bufLen = len * 2;

		if (bufLen < 0) {

			bufLen = Integer.MAX_VALUE;

		}

		StringBuffer outBuffer = new StringBuffer(bufLen);

		for (int x = 0; x < len; x++) {

			char aChar = theString.charAt(x);

			// Handle common case first, selecting largest block that

			// avoids the specials below

			if ((aChar > 61) && (aChar < 127)) {

				if (aChar == '\\') {

					outBuffer.append('\\');

					outBuffer.append('\\');

					continue;

				}

				outBuffer.append(aChar);

				continue;

			}

			switch (aChar) {

			case ' ':

				if (x == 0 || escapeSpace)
					outBuffer.append('\\');

				outBuffer.append(' ');

				break;

			case '\t':

				outBuffer.append('\\');

				outBuffer.append('t');

				break;

			case '\n':

				outBuffer.append('\\');

				outBuffer.append('n');

				break;

			case '\r':

				outBuffer.append('\\');

				outBuffer.append('r');

				break;

			case '\f':

				outBuffer.append('\\');

				outBuffer.append('f');

				break;

			case '=': // Fall through

			case ':': // Fall through

			case '#': // Fall through

			case '!':

				outBuffer.append('\\');

				outBuffer.append(aChar);

				break;

			default:

				if ((aChar < 0x0020) || (aChar > 0x007e)) {

					// 每个unicode有16位，每四位对应的16进制从高位保存到低位

					outBuffer.append('\\');

					outBuffer.append('u');

					outBuffer.append(toHex((aChar >> 12) & 0xF));

					outBuffer.append(toHex((aChar >> 8) & 0xF));

					outBuffer.append(toHex((aChar >> 4) & 0xF));

					outBuffer.append(toHex(aChar & 0xF));

				} else {

					outBuffer.append(aChar);

				}

			}

		}
		return outBuffer.toString();

	}

	public static String toStringToUtf(String str) {
		String newstr = "";
		if ("" != str && null != str) {
			char[] c = str.toCharArray();
			for (int i = 0; i < c.length; i++) {
				newstr += c[i];
			}
		}
		return newstr;
	}

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		toUtf8String toUtf8String = new toUtf8String();
		String str = toUtf8String.toEncodedUnicode("我", true);
		String newstr=toUtf8String.toStringToUtf("\u6211");
		System.out.println(str);
		System.out.println(newstr);
	}

}
